Force-Feedback Machining Robot for Accurate Profile Copying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The accuracy of positioning by a robot is lower than that of a machine tool due to its lower rigidity, limiting its use to processes with moderate machining accuracy and small reaction forces, making it unsuitable for precise cutting operations like profile trimming or pocket machining that require larger machine tools.
Innovation Solution
A robot control system equipped with a force sensor and a rotating mechanism that adjusts the arm's movement based on measured forces to maintain precise control during profile copying, allowing for automatic control of the tool's speed and position to manage reaction forces effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a robot arm is used for profile copying, then the device complexity and cost are reduced, but the positioning accuracy and machining precision deteriorate due to lower rigidity
Solution Approach 1:
A force sensor is integrated into the robot arm to detect reaction forces during machining operations. The control system uses this feedback to automatically adjust the arm's movement and maintain optimal cutting conditions, compensating for the lower rigidity and achieving positioning accuracy comparable to traditional machine tools
Solution Approach 2:
The system transitions from static, pre-programmed robot movement to dynamic, real-time control where the robot arm's velocity and position are continuously adjusted based on detected reaction forces, enabling adaptive compensation for rigidity limitations
2Weight of moving object
If a robot arm with lower rigidity is used, then the device size and cost are reduced, but the ability to handle large reaction forces deteriorates
Solution Approach 1:
The force sensor detects reaction forces in real-time, and the control system automatically reduces the robot arm's velocity when excessive force is detected, preventing damage to the less rigid robot arm while maintaining machining capability
Solution Approach 2:
The system dynamically changes the operating parameters (velocity, feed rate) of the robot arm based on the detected reaction forces, allowing the use of a smaller, less rigid arm while still handling machining operations that generate large forces
3Force
If manual copying with a hand router is used, then large reaction forces can be handled, but the productivity and machining consistency deteriorate due to reliance on worker skill
Solution Approach 1:
The robot system performs self-adjustment by automatically modifying its velocity based on reaction force feedback, eliminating the need for skilled manual operation while maintaining the ability to handle large forces and ensuring consistent machining quality
Solution Approach 2:
The patent replaces the manual mechanical control system with an automated control system that uses force sensor feedback to regulate the robot arm's movement, substituting human skill with automated sensing and control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables highly accurate machine cutting operations, such as profile trimming and pocket machining, with large reaction forces, even with a less rigid robot arm, achieving machining accuracy comparable to machine tools and improving efficiency by adjusting speeds to prevent excessive force and vibrations.
Implementation Method 1
a force measured by a force sensor configured to measure at least a force applied from the tool to the arm
Data Source
AI summary
A robot control system according to an embodiment is a control system for a robot comprising an arm, the arm being capable of holding a tool while rotating the tool and capable of moving the tool in at least two-dimensional directions, the arm being equipped with a rotating mechanism provided for the tool. The robot control system comprises a load-acquiring unit and a control-signal-generating unit. The load-acquiring unit is configured to acquire a force measured by a force sensor configured to measure a force applied from the tool to the arm during profile copying performed on a machining object by moving the arm while a copying guide attached to the arm and a copying mold placed on the machining object are kept in contact with each other. The control-signal-generating unit is configured to automatically control the arm by generating a control signal for the arm in accordance with the force acquired by the load-acquiring unit and with control information for the arm regarding the profile copying, and by outputting the control signal to the arm.